Defense that is filled?
Are you serious?
Every position is filled throughout the year, and guess what? It's the GM's job to replace players, either through trade, demotion, retirement, or releasing from UFA/RFA.
If they took your approach, teams wouldn't change for years.
If a GM isn't constantly trying to upgrade every position they can, they aren't doing their job.
That's the most idiotic logic I've ever seen.
This x10000